Lecture

Electroacoustics: Notions of Acoustics

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In course

EE-348: Electroacoustics

Ce cours a pour objectif de former les étudiants de section Génie Electrique et Electronique à la conception de systèmes acoustiques, à l'aide d'un formalisme basé sur l'électrotechnique. A la fin du semestre, les étudiants seront capables de dimensionner, ...

Description

This lecture covers the fundamental concepts of electroacoustics, including frequency response, sensitivity, efficiency, power, intensity, and directivity. It explains the characteristics of electroacoustic systems, transfer functions, and the basics of electrical quantities. The course also introduces the concept of decibel and its application in acoustics. The lecture delves into the analysis of signals, mechanical quantities, and the efficiency of electroacoustic systems. It discusses the importance of frequency in sinusoidal signals and the use of Fourier analysis. Additionally, it explores the impact of noise, harmonic distortion, and dynamic range in electroacoustic systems.

Instructor

Hervé Lissek

Expertise Acoustics and audio engineering, Electroacoustics.Room acoustics.Active noise control.Acoustic metamaterials.Assisted reverberation.Psychoacoustics.Sound spatialization Expertise Acoustics and audio engineering, Electroacoustics.Room acoustics.Active noise control.Acoustic metamaterials.Assisted reverberation.Psychoacoustics.Sound spatialization Mission Head of the Acoustic Group at the Laboratory of Wave Engineering LWE. Research topics :Active Electroacoustic Resonators: turning conventional lou

Official source

Ontological neighbourhood

Mechanical engineering

Acoustical engineering: Audio engineering

Related concepts (30)

Decibel

The decibel (symbol: dB) is a relative unit of measurement equal to one tenth of a bel (B). It expresses the ratio of two values of a power or root-power quantity on a logarithmic scale. Two signals whose levels differ by one decibel have a power ratio of 101/10 (approximately 1.26) or root-power ratio of 10 (approximately 1.12). The unit expresses a relative change or an absolute value. In the latter case, the numeric value expresses the ratio of a value to a fixed reference value; when used in this way, the unit symbol is often suffixed with letter codes that indicate the reference value.

Transfer function

In engineering, a transfer function (also known as system function or network function) of a system, sub-system, or component is a mathematical function that models the system's output for each possible input. They are widely used in electronic engineering tools like circuit simulators and control systems. In some simple cases, this function can be represented as two-dimensional graph of an independent scalar input versus the dependent scalar output, called a transfer curve or characteristic curve.

Dynamic range

Dynamic range (abbreviated DR, DNR, or DYR) is the ratio between the largest and smallest values that a certain quantity can assume. It is often used in the context of signals, like sound and light. It is measured either as a ratio or as a base-10 (decibel) or base-2 (doublings, bits or stops) logarithmic value of the difference between the smallest and largest signal values. Electronically reproduced audio and video is often processed to fit the original material with a wide dynamic range into a narrower recorded dynamic range that can more easily be stored and reproduced; this processing is called dynamic range compression.

Fourier analysis

In mathematics, Fourier analysis (ˈfʊrieɪ,_-iər) is the study of the way general functions may be represented or approximated by sums of simpler trigonometric functions. Fourier analysis grew from the study of Fourier series, and is named after Joseph Fourier, who showed that representing a function as a sum of trigonometric functions greatly simplifies the study of heat transfer. The subject of Fourier analysis encompasses a vast spectrum of mathematics.

Frequency

Frequency (symbol f) is the number of occurrences of a repeating event per unit of time. It is also occasionally referred to as temporal frequency for clarity and to distinguish it from spatial frequency. Frequency is measured in hertz (symbol Hz) which is equal to one event per second. Ordinary frequency is related to angular frequency (symbol ω, in radians per second) by a scaling factor of 2π. The period (symbol T) is the interval of time between events, so the period is the reciprocal of the frequency, f=1/T.

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